Resumable File Uploads with tus Protocol — JavaScript Guide

import * as tus from 'tus-js-client';

export function startResumableUpload(file: File, endpoint: string) {
  const upload = new tus.Upload(file, {
    endpoint: endpoint, // e.g. https://upload.example.com/files/
    retryDelays: [0, 1000, 3000, 5000],
    chunkSize: 5 * 1024 * 1024, // 5MB chunks
    metadata: {
      filename: file.name,
      filetype: file.type,
    },
    onError: (error) => {
      console.error('Upload failed:', error);
    },
    onProgress: (bytesUploaded, bytesTotal) => {
      const percentage = ((bytesUploaded / bytesTotal) * 100).toFixed(2);
      console.log(`Uploaded ${bytesUploaded} of ${bytesTotal} bytes (${percentage}%)`);
    },
    onSuccess: () => {
      console.log('Upload finished! URL:', upload.url);
    },
  });

  // Check if a previous upload can be resumed
  upload.findPreviousUploads().then((previousUploads) => {
    if (previousUploads.length > 0) {
      upload.resumeFromPreviousUpload(previousUploads[0]);
    }
    upload.start();
  });

  return upload;
}